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Newborn disease screening increases survival, improves quality of life and reduces treatment costs for healthcare systems. Mass spectrometry (MS) is an effective method for metabolic screening. However, conventional analytical methods require biofluid handling and cooling conditions during transport, making the logistics difficult and expensive, especially for remote regions. 'Paper-spray' (PS) ionization generates a charged solvent spray from samples deposited on paper strips. Therefore, samples can be applied on a suitable matrix and shipped as dried spots to diagnostic laboratories with standard postal or messenger services. We built a robotic platform, the 'Open SprayBot', to automatically analyze paper-deposited samples via PS-MS and increase the sample throughput. The system is operated via RUMBA32 and Arduino Mega boards. A commercial syringe pump and power supply provide solvent application and electrical current required for PS-MS. The usability of the Open SprayBot was demonstrated by quantifying palmitoyl-l-carnitine, a common biomarker in newborn screening.
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Metabolomics is the large-scale study of small molecule metabolites within a biological system. It has applications in measuring dietary intake, predicting heart disease risk, and diagnosing cancer. Metabolites are often measured using high-end analytical tools such as mass spectrometers or large spectrophotometers. However, due to their size, cost, and need for skilled operators, using such equipment at the bedside is not practical. To address this issue, we have developed a low-cost, portable, optical color sensor platform for metabolite detection. This platform includes LEDs, sensors, microcontrollers, a power source, and a Bluetooth chip enclosed within a 3D-printed light-tight case. We evaluated the color sensor's performance using both a range of dyed water samples as well as well-established colorimetric reactions for specific metabolite detection. The sensor accurately measured creatinine, L-carnitine, ascorbate, and succinate well within normal human urine levels with accuracy and sensitivity equal to or better than a standard laboratory spectrophotometer. Our color sensor offers a cost-effective, portable alternative for measuring metabolites via colorimetric assays, thereby enabling low-cost, point-of-care metabolite testing.
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Técnicas Biosensibles , Colorimetría , Humanos , Sistemas de Atención de Punto , EspectrofotometríaRESUMEN
Cannabis is widely used for medicinal and recreational purposes. As a result, there is increased interest in its chemical components and their physiological effects. However, current information on cannabis chemistry is often outdated or scattered across many books and journals. To address this issue, we used modern metabolomics techniques and modern bioinformatics techniques to compile a comprehensive list of >6000 chemical constituents in commercial cannabis. The metabolomics methods included a combination of high- and low-resolution liquid chromatography-mass spectrometry (MS), gas chromatography-MS, and inductively coupled plasma-MS. The bioinformatics methods included computer-aided text mining and computational genome-scale metabolic inference. This information, along with detailed compound descriptions, physicochemical data, known physiological effects, protein targets, and referential compound spectra, has been made available through a publicly accessible database called the Cannabis Compound Database (https://cannabisdatabase.ca). Such a centralized, open-access resource should prove to be quite useful for the cannabis community.
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Cannabis , Cannabis/química , Metabolómica , Cromatografía de Gases y Espectrometría de Masas , Extractos Vegetales/química , Espectrometría de Masas , Biología ComputacionalRESUMEN
Maternal pathological conditions such as infections and chronic diseases, along with unexpected events during labor, can lead to life-threatening perinatal outcomes. These outcomes can have irreversible consequences throughout an individual's entire life. Urinary metabolomics can provide valuable insights into early physiological adaptations in healthy newborns, as well as metabolic disturbances in premature infants or infants with birth complications. In the present study, we measured 180 metabolites and metabolite ratios in the urine of 13 healthy (hospital-discharged) and 38 critically ill newborns (admitted to the neonatal intensive care unit (NICU)). We used an in-house-developed targeted tandem mass spectrometry (MS/MS)-based metabolomic assay (TMIC Mega) combining liquid chromatography (LC-MS/MS) and flow injection analysis (FIA-MS/MS) to quantitatively analyze up to 26 classes of compounds. Average urinary concentrations (and ranges) for 167 different metabolites from 38 critically ill NICU newborns during their first 24 h of life were determined. Similar sets of urinary values were determined for the 13 healthy newborns. These reference data have been uploaded to the Human Metabolome Database. Urinary concentrations and ranges of 37 metabolites are reported for the first time for newborns. Significant differences were found in the urinary levels of 44 metabolites between healthy newborns and those admitted at the NICU. Metabolites such as acylcarnitines, amino acids and derivatives, biogenic amines, sugars, and organic acids are dysregulated in newborns with bronchopulmonary dysplasia (BPD), asphyxia, or newborns exposed to SARS-CoV-2 during the intrauterine period. Urine can serve as a valuable source of information for understanding metabolic alterations associated with life-threatening perinatal outcomes.
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One of the major challenges currently faced by global health systems is the prolonged COVID-19 syndrome (also known as "long COVID") which has emerged as a consequence of the SARS-CoV-2 epidemic. It is estimated that at least 30% of patients who have had COVID-19 will develop long COVID. In this study, our goal was to assess the plasma metabolome in a total of 100 samples collected from healthy controls, COVID-19 patients, and long COVID patients recruited in Mexico between 2020 and 2022. A targeted metabolomics approach using a combination of LC-MS/MS and FIA MS/MS was performed to quantify 108 metabolites. IL-17 and leptin were measured in long COVID patients by immunoenzymatic assay. The comparison of paired COVID-19/long COVID-19 samples revealed 53 metabolites that were statistically different. Compared to controls, 27 metabolites remained dysregulated even after two years. Post-COVID-19 patients displayed a heterogeneous metabolic profile. Lactic acid, lactate/pyruvate ratio, ornithine/citrulline ratio, and arginine were identified as the most relevant metabolites for distinguishing patients with more complicated long COVID evolution. Additionally, IL-17 levels were significantly increased in these patients. Mitochondrial dysfunction, redox state imbalance, impaired energy metabolism, and chronic immune dysregulation are likely to be the main hallmarks of long COVID even two years after acute COVID-19 infection.
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COVID-19 , Interleucina-17 , Humanos , Espectrometría de Masas en Tándem , Cromatografía Liquida , SARS-CoV-2 , Metaboloma , Metabolómica , Síndrome Post Agudo de COVID-19RESUMEN
The Human Metabolome Database or HMDB (https://hmdb.ca) has been providing comprehensive reference information about human metabolites and their associated biological, physiological and chemical properties since 2007. Over the past 15 years, the HMDB has grown and evolved significantly to meet the needs of the metabolomics community and respond to continuing changes in internet and computing technology. This year's update, HMDB 5.0, brings a number of important improvements and upgrades to the database. These should make the HMDB more useful and more appealing to a larger cross-section of users. In particular, these improvements include: (i) a significant increase in the number of metabolite entries (from 114 100 to 217 920 compounds); (ii) enhancements to the quality and depth of metabolite descriptions; (iii) the addition of new structure, spectral and pathway visualization tools; (iv) the inclusion of many new and much more accurately predicted spectral data sets, including predicted NMR spectra, more accurately predicted MS spectra, predicted retention indices and predicted collision cross section data and (v) enhancements to the HMDB's search functions to facilitate better compound identification. Many other minor improvements and updates to the content, the interface, and general performance of the HMDB website have also been made. Overall, we believe these upgrades and updates should greatly enhance the HMDB's ease of use and its potential applications not only in human metabolomics but also in exposomics, lipidomics, nutritional science, biochemistry and clinical chemistry.
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Bases de Datos Genéticas , Metaboloma/genética , Metabolómica/clasificación , Humanos , Lipidómica/clasificación , Espectrometría de Masas , Interfaz Usuario-ComputadorRESUMEN
The Natural Products Magnetic Resonance Database (NP-MRD) is a comprehensive, freely available electronic resource for the deposition, distribution, searching and retrieval of nuclear magnetic resonance (NMR) data on natural products, metabolites and other biologically derived chemicals. NMR spectroscopy has long been viewed as the 'gold standard' for the structure determination of novel natural products and novel metabolites. NMR is also widely used in natural product dereplication and the characterization of biofluid mixtures (metabolomics). All of these NMR applications require large collections of high quality, well-annotated, referential NMR spectra of pure compounds. Unfortunately, referential NMR spectral collections for natural products are quite limited. It is because of the critical need for dedicated, open access natural product NMR resources that the NP-MRD was funded by the National Institute of Health (NIH). Since its launch in 2020, the NP-MRD has grown quickly to become the world's largest repository for NMR data on natural products and other biological substances. It currently contains both structural and NMR data for nearly 41,000 natural product compounds from >7400 different living species. All structural, spectroscopic and descriptive data in the NP-MRD is interactively viewable, searchable and fully downloadable in multiple formats. Extensive hyperlinks to other databases of relevance are also provided. The NP-MRD also supports community deposition of NMR assignments and NMR spectra (1D and 2D) of natural products and related meta-data. The deposition system performs extensive data enrichment, automated data format conversion and spectral/assignment evaluation. Details of these database features, how they are implemented and plans for future upgrades are also provided. The NP-MRD is available at https://np-mrd.org.
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Productos Biológicos/química , Bases de Datos Factuales , Espectroscopía de Resonancia Magnética , Programas Informáticos , Productos Biológicos/clasificación , InternetRESUMEN
BACKGROUND/AIMS: Diastolic dysfunction (DD) and low levels of thyroid hormones (TH) are frequent found in chronic kidney disease; both are associated with all-cause and cardiovascular mortality. However, a link between them has not yet been established. The aim of this study was to analyze DD as a surrogate marker of fibrosis and its association with TH in incident patients on peritoneal dialysis (PD). METHODS: A cross-sectional study with 183 incident patients on PD with preserved ejection fraction was performed. Clinical and demographic data were registered. Serum total and free (t/f) triiodothyronine (T3), thyroxin (T4), and thyroid stimulating hormone levels were determined by RIA kits, albumin and high-sensitivity C-reactive protein by conventional assays. Transthoracic 2D echocardiogram was performed for evaluation of left ventricular (LV) mass and ejection fraction. DD was evaluated using pulsed-wave tissue Doppler imaging. RESULTS: Patients were 43 ± 12, 42% with diabetes mellitus (DM). Some degree of DD was found in 62% of patients; 18% had grade I DD, 8% grade II DD and 36% grade III DD. Patients with grade III DD were more likely to have diabetes, older, high LV mass and low serum albumin, t/fT3 and tT4 levels. In logistic multivariate regression analysis, it was found that diabetes (B = -0.86, 95% CI 0.182-0.992, p < 0.05), hypertension (B = -0.95, 95% CI 0.184-0.817, p = 0.01) and tT3 (B = -1.94, 95% CI 0.023-0.876, p < 0.05) were associated with grade III DD. CONCLUSIONS: High prevalence of grade III DD was found in incident patients on PD. In addition to DM and hypertension, tT3 was found to be an independent risk factor for grade III DD and more studies are needed to understand the reasons as to why this association is present.
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Diástole/fisiología , Diálisis Peritoneal/efectos adversos , Hormonas Tiroideas/deficiencia , Disfunción Ventricular Izquierda/etiología , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/terapia , Factores de Riesgo , Disfunción Ventricular Izquierda/epidemiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
Vinasse is the dark-colored wastewater that is generated by bioethanol distilleries from feedstock molasses. The vinasse that is generated from molasses contains high amounts of pollutants, including phenolic compounds and melanoindin. The goal of this work was to study the expression of laccase genes in the Trametes hirsuta strain Bm-2, isolated in Yucatan, Mexico, in the presence of phenolic compounds, as well as its effectiveness in removing colorants from vinasse. In the presence of all phenolic compounds tested (guaiacol, ferulic acid, and vanillic acid), increased levels of laccase-encoding mRNA were observed. Transcript levels in the presence of guaiacol were 40 times higher than those in the control. The lcc1 and lcc2 genes of T. hirsuta were differentially expressed; guaiacol and vanillin induced the expression of both genes, whereas ferulic acid only induced the expression of lcc2. The discoloration of vinasse was concomitant with the increase in laccase activity. The highest value of enzyme activity (2543.7 U/mL) was obtained in 10% (v/v) vinasse, which corresponded to a 69.2% increase in discoloration. This study demonstrates the potential of the Bm-2 strain of T. hirsuta for the biodegradation of vinasse.
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Regulación Fúngica de la Expresión Génica , Residuos Industriales , Lacasa/genética , Trametes/enzimología , Trametes/genética , Aguas Residuales/microbiología , Biodegradación Ambiental , Genes Fúngicos , Lacasa/metabolismo , Fenoles/aislamiento & purificación , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
This study characterized Clavispora lusitaniae strains isolated from different stages of the processing and early fermentation of a henequen (Agave fourcroydes) spirit produced in Yucatan, Mexico using a molecular technique. Sixteen strains identified based on morphological features, obtained from different substrates, were typed molecularly. Nine different versions of the divergent D1/D2 domain of the large-subunit ribosomal DNA sequence were identified among the C. lusitaniae strains. The greatest degree of polymorphism was found in the 90-bp structural motif of the D2 domain. The MSP-PCR technique was able to differentiate 100% of the isolates. This study provides significant insight into the genetic diversity of the mycobiota present during the henequen fermentation process, especially that of C. lusitaniae, for which only a few studies in plants have been published. The applied MSP-PCR markers were very efficient in revealing olymorphisms between isolates of this species.
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Agave/microbiología , Bebidas Alcohólicas/microbiología , Dermatoglifia del ADN , ADN de Hongos/genética , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , ADN Ribosómico , Fermentación , Variación Genética , México , Microbiota , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Saccharomycetales/clasificación , Análisis de Secuencia de ADNRESUMEN
(-)-Epicatechin (EPI) is cardioprotective in the setting of ischemia/reperfusion (IR) injury and doxycycline (DOX) is known to preserve cardiac structure/function after myocardial infarction (MI). The main objective of this study was to examine the effects of EPI and DOX co-administration on MI size after IR injury and to determine if cardioprotection may involve the mitigation of mitochondrial swelling. For this purpose, a rat model of IR was used. Animals were subjected to a temporary 45 min occlusion of the left anterior descending coronary artery. Treatment consisted of a single or double dose of EPI (10 mg/kg) combined with DOX (5 mg/kg). The first dose was given 15 min prior to reperfusion and the second 12 h post-MI. The effects of EPI +/- DOX on mitochondrial swelling (i.e. mPTP opening) were determined using isolated mitochondria exposed to calcium overload and data examined using isobolographic analysis. To ascertain for the specificity of EPI effects on mitochondrial swelling other flavonoids were also evaluated. Single dose treatment reduced MI size by ~46% at 48 h and 44% at three weeks. Double dosing evidenced a synergistic, 82% reduction at 3 weeks. EPI plus DOX also inhibited mitochondrial swelling in a synergic manner thus, possibly accounting for the cardioprotective effects whereas limited efficacy was observed with the other flavonoids. Given the apparent lack of toxicity in humans, the combination of EPI and DOX may have clinical potential for the treatment of myocardial IR injury.
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Catequina/farmacología , Doxiciclina/farmacología , Flavonoides/farmacología , Dilatación Mitocondrial/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológico , Daño por Reperfusión/tratamiento farmacológico , Animales , Cardiotónicos/farmacología , Vasos Coronarios/efectos de los fármacos , Sinergismo Farmacológico , Masculino , Mitocondrias Cardíacas/efectos de los fármacos , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: C. gloeosporioides sensu lato is one of the most economically important post-harvest diseases affecting papaya production worldwide. There is currently no information concerning the genetic structure or demographic history of this pathogen in any of the affected countries. Knowledge of molecular demographic parameters for different populations will improve our understanding of the biogeographic history as well as the evolutionary and adaptive potential of these pathogens. In this study, sequence data for ACT, GPDH, ß-TUB and ITS gene regions were analyzed for C. gloeosporioides sensu lato and C. truncatum isolates infecting papaya in Trinidad and Mexico in order to determine the genetic structure and demographic history of these populations. RESULTS: The data indicated that Mexico is the ancestral C. gloeosporioides sensu lato population with asymmetrical migration to Trinidad. Mexico also had the larger effective population size but, both Mexico and Trinidad populations exhibited population expansion. Mexico also had greater nucleotide diversity and high levels of diversity for each gene. There was significant sub-division of the Trinidad and Mexico populations and low levels of genetic divergence among populations for three of the four gene regions; ß-TUB was shown to be under positive selection. There were also dissimilar haplotype characteristics for both populations. Mutation may play a role in shaping the population structure of C. gloeosporioides sensu lato isolates from Trinidad and from Mexico, especially with respect to the ACT and GPDH gene regions. There was no evidence of gene flow between the C. truncatum populations and it is possible that the Mexico and Trinidad populations emerged independently of each other. CONCLUSIONS: The study revealed relevant information based on the genetic structure as well as the demographic history of two fungal pathogens infecting papaya, C. gloeosporioides sensu lato and C. truncatum, in Trinidad and Mexico. Understanding the genetic structure of pathogen populations will assist in determining the evolutionary potential of the pathogen and in identifying which evolutionary forces may have the greatest impact on durability of resistance. Intervention strategies that target these evolutionary forces would prove to be the most practical.
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Carica/microbiología , Colletotrichum/genética , Evolución Molecular , Enfermedades de las Plantas/microbiología , Secuencia de Bases , Colletotrichum/clasificación , Colletotrichum/aislamiento & purificación , Estructuras Genéticas , México , Datos de Secuencia Molecular , Filogenia , Trinidad y TobagoRESUMEN
BACKGROUND: The possibility of decreasing or reverting left ventricular hypertrophy and, therefore, cardiac hypertrophy (CH) is an important medical issue. The aim of the present study was to evaluate these two possibilities with a 3-week daily dose of captopril, losartan, or bromocriptine in a preventive or corrective model. METHODS: After aorto caval fistulae (ACF) surgery on adult male Wistar rats to induce CH, animals were assigned to the preventive protocol (drug treatment began immediately after surgery) or corrective protocol (hypertrophy was allowed to develop before drug treatment). After treatments, isoproterenol was administered to half of the animals to further induce CH. The groups included the passive control, the sham-operated animals, those with ACF surgery but without drug treatment, and the 3-week treatments with captopril, losartan, or the low or high dose of bromocriptine. RESULTS: Three treatments, with captopril, losartan, or the high dose of bromocriptine, significantly impeded/reverted an increase in CH-related parameters in the preventive/corrective model compared to the surgically treated group without drug treatment. The same effect was found after isoproterenol administration. The present results show an avoidance/reversion of CH with these three treatments. Better results were found with the angiotensin converting enzyme inhibitor (captopril) than with the prolactin inhibitor (bromocriptine). CONCLUSIONS: Treatments with captopril, losartan, and the high dose of bromocriptine were effective in preventing/reversing the manifestation of CH in the preventive/corrective rat models. Further studies are needed to identify the initial mediator, the key component, and the molecular events involved in the pathogenesis of CH.
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Cardiomegalia/prevención & control , Prolactina/antagonistas & inhibidores , Animales , Enfermedades de la Aorta/complicaciones , Fístula Arteriovenosa/complicaciones , Presión Sanguínea/efectos de los fármacos , Bromocriptina/administración & dosificación , Captopril/administración & dosificación , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/patología , Modelos Animales de Enfermedad , Antagonistas de Hormonas/administración & dosificación , Humanos , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Izquierda/prevención & control , Losartán/administración & dosificación , Masculino , Ratas , Ratas Wistar , Vena Cava InferiorRESUMEN
BACKGROUND: Residual renal function (RRF) is an important determinant of mortality and morbidity in patients receiving peritoneal dialysis (PD). Recent studies have shown a positive effect of angiotensin converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARBs) on RRF in PD patients. OBJECTIVE: To compare enalapril and losartan for RRF preservation in automated peritoneal dialysis (APD) patients. MATERIAL AND METHODS: An open label randomized controlled trial (RCT) with a 12 month follow-up period was conducted to compare the effect of enalapril vs. losartan on RRF preservation in 60 APD patients. Measurements were done at the start of the study (baseline), 3, 6, 9, and 12 months. A historical control group (HCG) without treatment was included to assess the natural history of RRF loss. RESULTS: RRF in the enalapril group dropped from 3.65 +/- 1.6 (baseline) to 2.36 +/- 0.38 mL/min/1.73 m2 (12 months). In the losartan group RRF was reduced from 4.1+/- 2.01 (baseline) to 2.54 +/- 0.47 mL/min/ 1.73 m2 (12 months). There were not significant differences between the two groups regarding RRF at 12 months. In the HCG, RRF declined from 3.68 +/- 0.48 to 1.4 +/- 0.29 mL/min/ 1.73 m2 (12 months). RRF in the HCG was significantly lower than RRF in the two treated groups at 12 months (P < 0.05). CONCLUSIONS: There was not significant difference on RRF preservation between enalapril and losartan groups. Comparing these results to those of the HCG suggests that the treatment with any of the drugs is useful in preserving RRF.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Enalapril/farmacología , Fallo Renal Crónico/fisiopatología , Riñón/efectos de los fármacos , Losartán/farmacología , Tasa de Depuración Metabólica/efectos de los fármacos , Diálisis Peritoneal , Adulto , Anciano , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Glucemia/análisis , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Creatinina/orina , Progresión de la Enfermedad , Enalapril/uso terapéutico , Femenino , Humanos , Riñón/fisiopatología , Fallo Renal Crónico/tratamiento farmacológico , Fallo Renal Crónico/terapia , Losartán/uso terapéutico , Masculino , Persona de Mediana Edad , Diálisis Peritoneal/métodos , Estudios Prospectivos , Urea/sangre , Urea/orina , Adulto JovenRESUMEN
It has been postulated that in blood vessels under alpha(1)-related stimulation, the endothelial intracellular calcium concentration ([Ca(2+)](i)) increases, which is necessary to induce nitric oxide synthesis, is the result of an increase in vascular smooth muscle, which subsequently, flows into the endothelial cells through gap junctions and it is not the result of a direct adrenergic stimulation of endothelial receptors. Others, however, postulate that endothelial alpha(1D)-adrenoceptors, have a direct effect on nitric oxide synthesis. In order to clarify this phenomena, in this work we analyzed the presence of alpha(1)receptor subtypes and their functional association with nitric oxide synthesis in rat coronary microvascular endothelial cells in culture, with pharmacological, immunological and reverse transcriptase polymerase chain reaction approaches. Our results show the presence and functional coupling with nitric oxide synthesis of alpha(1A) and alpha(1D)-adrenoceptor subtypes. alpha(1B)-adrenoceptor subtype is not coupled with nitric oxide production.
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Vasos Coronarios/química , Células Endoteliales/química , Receptores Adrenérgicos alfa 1/análisis , Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Animales , Bradiquinina/farmacología , Células Cultivadas , Vasos Coronarios/citología , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Inhibidores Enzimáticos/farmacología , Técnica del Anticuerpo Fluorescente Indirecta , Immunoblotting , Masculino , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa/antagonistas & inhibidores , Fenilefrina/farmacología , ARN Mensajero/análisis , Ratas , Ratas Wistar , Receptores Adrenérgicos alfa 1/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Caveolins are a family of integral membrane proteins implicated in various cell functions, including the organization and inactivation of signaling molecules of G protein-coupled receptors. We tested the ability of human caveolin scaffolding peptide-1 (CSP-1) to regulate norepinephrine- (NE) or histamine (HIS)-induced increases on intracellular calcium concentrations ([Ca(2+)]i). In cultured rat vascular smooth muscle cells (VSMC), CSP-1 inhibited in a concentration-dependent manner NE- and HIS-induced increases in [Ca(2+)]i. This effect can be explained by the fact that CSP-1 inhibited a common signaling pathway. We tested the ability of this peptide to decrease the activation of PLC-beta3 and MAPK. CSP-1 inhibited the expression of the activated form of both enzymes, suggesting a direct effect of the peptide on the signaling cascade. CSP-1 readily enters VSMC in culture, as observed when FITC-conjugated CPS-1 is added to cell culture media. Taken together, these data suggest that CSP-1 blocks the effects of NE and HIS on [Ca(2+)]i of VSMC by inhibiting the activation of PLC-beta3 and MAPK.
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Caveolina 1/farmacología , Isoenzimas/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Norepinefrina/farmacología , Fosfolipasas de Tipo C/metabolismo , Animales , Calcio/metabolismo , Células Cultivadas , Interacciones Farmacológicas , Activación Enzimática/efectos de los fármacos , Fluoresceína-5-Isotiocianato/metabolismo , Histamina/farmacología , Humanos , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Miocitos del Músculo Liso/enzimología , Miocitos del Músculo Liso/metabolismo , Fosfolipasa C beta , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacosRESUMEN
The objective of this work was to evaluate the effects of testosterone (T) and 17beta-estradiol (E(2)) on coronary microvascular endothelial cells (CMECs) of male and female rats. To analyze the short-term effects of such sex steroid hormones on intracellular Ca(2+) concentration ([Ca(2+)](i)) kinetics, we used the chelating agent fura-2 acetoxymethyl ester. We also explored the possibility of testosterone aromatization by using selective inhibitors of the aromatase enzyme cytochrome P-450 aromatase (P450(arom)), aminoglutethimide (4 microM), and 4-hydroxyandrostenedione (4 microM). The presence of P450(arom) was investigated by immunocytochemical and immunoblot assays using peptide-generated polyclonal antibodies raised against a 20-amino acid synthetic fragment of rat P450(arom) and by in situ hybridization to locate the aromatase mRNA in such cells. The activity of P450(arom) was demonstrated by the stereospecific loss of the tritium atom of [1beta-(3)H]androstenedione. Our results indicate that both T and E(2) induced a rapid increase in [Ca(2+)](i). The fact that the effects of E(2) and T were carried out within milliseconds suggests that they were exerted at the membrane level and not through intracellular receptors. The possibility of involvement of PLC-beta in these effects is suggested because U-73122 (a PLC inhibitor) blocked the effects of both T and E(2). Immunocytochemical assays indicated the expression of androgenic and estrogenic receptors in these cells. The effects of T were blocked by the selective aromatase inhibitors. We also demonstrated membrane association of P450(arom), expression of the ovary-specific mRNA after in situ hybridization, and E(2) formation resulting from a significant activity of P450(arom) in CMECs. There were no gender-based differences.